Helping Dalia Bloom

Massive System

Representing an estimated development investment of US$3.4 billion (NOK 28.8 billion), the sheer scope of the Dalia development, coupled with the complex challenges associated with the extreme environment, requires technical innovation and expertise at the forefront of the offshore industry. The massive subsea system currently comprises a planned 67 wells, with discussions ongoing to increase to 71.

Discovered near the Girassol field in Block 17, Dalia is located in water depths of between 4,000 - 5,000 ft (1,200 - 1,500 m), 84 miles (135 km) offshore Angola. It is the next of the major "flower" fields and follows the successful development of Girassol, brought on stream in late 2001, and Jasmim, a satellite to the Girassol field, which began production in the second half of 2003. Total and its partners ExxonMobil, BP, Statoil and Hydro see the launch of Dalia, due on-stream during the second half of 2006, as a key step in the development of the deepwater Block 17.

At the end of 2002, Total and Sonangol awarded the contract that enabled the start of pre-engineering activities for the Dalia Subsea Production System. The EPC contract for the subsea oil production system followed in April 2003.

The project scope covers engineering, procurement and fabrication for all necessary subsea production equipment. Today, this includes 67 christmas trees and wellhead systems - 34 production wells, 30 water injection wells and three gas injection wells - plus nine manifolds, two work over systems and all related connection systems. The equipment is being delivered based on various call-offs that began with an initial contract for 42 trees with options for additional trees.

According to Daniel Picard, Dalia's Project Director at Total, "With nearly twice the number of wells as Girassol, Dalia is technically more challenging. We are also dealing with a fluid that is much more complex - at 21° API (American Petroleum Institute), as opposed to 32° API on Girassol, the oil is heavier. We need to keep it hot enough so that it can flow from the reservoir to the FPSO vessel. With relatively low reservoir temperatures, the temperature window is a lot narrower, so we have huge constraints relating to flow assurance, which are extremely demanding."

Shallow water testing of the equipment took place in Spain and included tests designed to ensure that all of the temperature constraints are met. Hot fluids, for example, were placed in components of the subsea equipment to check flow assurance and temperature controls. Christmas trees, control systems, manifolds, jumpers and spools - every representative piece of the subsea process system - is tested to ensure everything works smoothly once installed. In such a complex subsea system, accessibility to equipment on the seabed is naturally much more difficult, making these precautions even more paramount.

Raymond Carlsen, Group EVP and President of Kvaerner Oilfield Products, says, "The Dalia contract represents a major breakthrough for us in the very demanding market offshore West Africa. While we have delivered complex subsea production systems before, Dalia is challenging - in terms of the extreme conditions of the field's location, the type of crude oil to be handled, and the sheer scale of the project."

With the studies and procurement completed, fabrication of various elements of the subsea process system began in order to meet Total’s goal to start drilling at the beginning of 2005, earlier than originally planned. The equipment fabrication schedule was specifically timed to provide Total with a big enough window to drill sufficient wells in order achieve first oil in the second half of 2006.

In January 2004, Total commissioned fabrication of the FPSO hull in Korea, which was completed in the third quarter. Construction of the 30,000 tonnes of topsides was also carried out in Korea. Engineering, procurement and manufacture of the umbilical and flowlines was also progressed during this period. Aker Kvaerner’s Tranby factory in Norway is handling the manufacture and assembly of the subsea christmas trees, and fabrication and assembly of the controls components are being handled out of Aberdeen in the UK.

A further significant element is the Angolan content, which has seen involvement by the Lobito Sonamet yard, a joint venture between Sonangol and service company Stolt Offshore, where assembly of six manifolds and all the related seabed support systems is being carried out.

With different packages being handled in Angola and around the world, developing effective interfaces with local and other contractors, as well as between the various project offices and fabrication units, has also been a fundamental factor for success.

"The challenge is to ensure the right information is transferred to the right parties at the right time, so good communication is vital," remarks Carlsen. "Right from the start, we knew we had to quickly learn how Total likes to run its projects and to completely understand the criteria under which this field has to be developed. Total is very focused on delivering their commitments and developing the field, and so are we."

A large part of the contract is the fabrication and supply of the system, but the other key element is the service and assistance that will be provided when the equipment is installed. A team from Aker Kvaerner will be present to advise the installation contractor every step of the way and at the start-up phase. The company will also be available after start-up to provide assistance with maintenance and life-of-field support.

With the life span of the field expected to be some 20 years, it is important that Dalia has the correctly trained people and the right management in place to achieve future production objectives. More than a dozen young Angolan engineers have been undergoing training, at Aker Kvaerner facilities in Norway and Scotland, so that they are ready when the field comes on-stream in 2006.

"Right from the outset, we made a firm commitment to deliver the necessary training to build local competence and technical knowledge," Carlsen explains. "We started training Angolans almost four years ago to make certain they have the necessary offshore and onshore expertise. This has involved exposing them to different disciplines across different parts of the company - integrating them with our teams in Oslo and Aberdeen."

Significant parts of the project are being handled in Luanda, in the offices of the Aker Kvaerner joint venture with local architectural and civil engineering company SOAPRO. This joint venture will serve to assist Total and other clients’ projects with their subsea requirements, and related areas. A new, modern maintenance base has been established in Luanda, giving the company a sound platform from which to develop its service offering and local competence in the region.

"West Africa offers major growth opportunities for our business, so our investment in Angola provides a base for future expansion," adds Carlsen. "We need to offer predictability to all our clients. So Dalia is a very important project reference for us. There are also promising oil discoveries on Block 32, where water depths go to some 8,850 ft (2,700 m). We are one of the few companies that have qualified trees at that water depth."

Total's worldwide strategy is to continue to increase production, and West Africa plays a significant role in helping to fulfill these goals. "We've stated clearly that we will continue to increase production at a rate of four percent over the next five years. It's therefore essential to us that sufficient fields come on-stream in the desired timeframe to achieve these levels.

"The Dalia field is an important part of that overall strategy and current expectations are that it will deliver 225,000 barrels per day (1,500 m3/hr). We are also in discussions to see that increase to 240,000 bpd (1,600 m3/hr) during the plateau life of the field," says Picard.

"We need to be able to supplement our resources by having competent contractors, as we have on this project. We realise the logistics are difficult, but we have a close dialogue and that's essential. We have easy access to the project team and to Raymond and the rest of Aker Kvaerner's senior management, which is very helpful and reassuring in such a large project. We have different reasons for wishing to deliver this project well but, above all, we all want to get there," Picard concludes.